Evaporator assembly



y R. MCGREGOR EVAPORATOR ASSEMBLY 2 Sheets-Sheet 1 Filed Nov. 17, 1952INVENTOR.

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May 24, 1955 R. M GREGOR EVAPORATOR ASSEMBLY 2 Sheets-Sheet 2 Filed Nov.17, 1952 IN VEN TOR.

P41 PH M G/?6 BY v/mmw ATTOK/V 5 United States Patent EVAPORATORASSEMBLY Ralph McGregor, Libertyville, 111., assia'uor to Motor ProductsCorporation, Detroit, Mich., a corporation of New York ApplicationNovember 17, 1952, Serial No. 320,851

2 Claims. (Cl. 62126) liquid refrigerant through the evaporator in sucha manner that the liquid refrigerant is entirely evaporated beforereaching the return line of the system. Thus maximum cooling is obtainedwith an evaporator of given size.

Another object of this invention is to provide an evaporator whereinliquid refrigerant is compelled to flow in a circuitous path through theevaporator shell by an arrangement of partitions or discs and wherein acertain amount of liquid refrigerant is retained in heat transferrelationship to the partitions or discs until it is evaporated.

A further object of this invention is to provide an evaporator of theforegoing type composed of a relatively few simple parts capable ofbeing inexpensively manufactured, assembled and installed.

The foregoing as well as other objects will be made more apparent asthis description proceeds especially when considered in connection withthe accompanying drawing, wherein:

Figure 1 is a semi-diagrammatic view of a refrigerating system having anevaporator constructed in accordance with this invention;

Figure 2 is a longitudinal sectional view through the evaporator shownin Figure 1;

Figure 3 is a cross sectional view taken substantially on the planeindicated by the line 3-3 of Figure l; and

Figure 4 is a view similar to Figure 2 showing a modified form ofconstruction.

Referring first to the embodiment of the invention shown in Figures 1-3inclusive, the numeral designates an evaporator comprising a cylindricalshell 11 having the upper end closed by a top wall 12 and having thelower end closed by a plug 13. The plug 13 is seated against an annularshoulder 14 formed on the shell at the lower end thereof and is held inengagement with the shoulder by a base plate 15. The base plate 15 isremovably secured to the plug 13 by screws 16 and is formed with ears 17which project laterally outwardly from the side wall of the shell 11.The ears 17 are spaced from each other circumferentially of the shelland each car has an opening therethrough for receiving an anchoring stud18.

The interior of the shell 11 is divided into vertically spaced chambers19 by sheet metal discs 20 having annular downturned flanges 21 at theperiphery thereof engageable with the inner surface of the shell 11 andhaving aligned openings through the central portions for receiving avertical stud 22. The discs 20 are spaced from each other axially of thestud 22 by a plurality of tubular spacers 23 respectively mounted on thestud between adjacent discs 20. The upper end of the stud is threadedinto the top wall 12 of the shell and a nut 24 is threaded on the lowerend of the stud in a position to engage the bottom disc 20. A tubularspacer 25 is mounted on the stud between the top disc 20 and the bottomsurface of the top wall 12 in a manner to coact with the nut 24 to clampthe discs in assembled relationship.

The chamber 19 formed by the space between the top disc 20 and the topwall 12 of the shell communicates with one end of a conduit 26 havingthe opposite end connected to the discharge side of a condenser 27through the medium of the usual capillary tube 28. The chamber 19 formedby the space between the bottom disc ice 20 and the plug 13 is connectedto one end of a conduit 29 having the opposite end connected to theintake side of a motor-compressor unit 30 through a suitable accumulator30'. The discharge side of the motor-compressor unit 30 is connected tothe intake side of the condenser 27 in accordance with the usualpractice. It follows from the above that liquid refrigerant isintroduced into the top chamber 19 of the evaporator through the conduit26 and gaseous refrigerant is discharged from the bottom chamber 19 ofthe evaporator to the motorcompressor unit 30.

In order to establish communication between the top and bottom chambers19 in the evaporator each of the discs 20 are formed with openings 31therethrough. The openings 31 in adjacent discs are staggered withrespect to one another and in the present instance are spaced 180 fromeach other so that the refrigerant flows in a circuitous path from thetop chamber 19 of the evaporator to the bottom chamber 19. Moreparticularly, the liquid refrigerant is compelled to flow substantiallyover the entire area of the discs 20 and as a result evaporation of theliquid refrigerant is expedited. In order to further insure completeevaporation of the liquid refrigerant within the evaporator a certainamount of the refrigerant is retained in the respective chambers 19.This is accomplished by forming each disc 20 with an annular upstandingflange 32 around the opening 31 therethrough. The flanges 32 trap acertain amount of liquid refrigerant in each of the chambers 19 andprovide in effect a flooded condition on the surfaces of the variousdiscs 20. In

4 other Words, a shallow pool of liquid refrigerant remains on each discuntil evaporation takes place and due to the relatively large area ofthe discs 20 the transfer of heat from the disc 20 to the liquidrefrigerant is accomplished expediently. Thus, it is possible to cool afood storage area of substantial size with a relatively small compactevaporator.

In the embodiment of the invention shown in Figure 4 of the drawing, atube 33 is substituted for the stud 22 and the evaporator discs 20 aremounted on the tube 33 in vertical spaced relationship in the samemanner described above. The tube 33 extends beyond opposite ends of theshell 11 and may be connected in a secondary refrigerating system (notshown) in a manner such that refrigerant from the secondary system isconducted through the evaporator 10 and cooled thereby.

What I claim as my invention is:

1. An evaporator for a refrigerating system, comprising a verticallyextending shell having a wall at one end closing the latter end of theshell, a closure for the opposite end of the shell formed separatelyfrom the shell, a plurality of discs of heat conducting materialsupported within the shell in vertical spaced relationship to each otherand to the ends of the shell, said disc having the outer edgesengageable with the inner surfaces of the shell and having alignedcentrally arranged openings therethrough, a tie member extendingvertically through the centrally aligned openings and clamped to theshell, tubular spacers supported on the tie member between adjacentdiscs for securing the latter on the tie member in proper verticalspaced relationship, a passage for refrigerant communicating with thespace between the end wall aforesaid of the shell and the adjacent disc,a second passage for refrigerant communicating with the space betweenthe closure and adjacent disc, each disc having an opening therethroughfor the passage of refrigerant and the openings through adjacent discsbeing staggered with respect to one another, and each disc having anupstanding flange encircling the opening therethrough.

2. The structure defined in claim 1 wherein the tie member comprises atube for conducting refrigerant through the shell, said tube extendingvertically through the centrally aligned openings in the discs andthrough the end Wall and closure at opposite ends of the shell,

and abutments on the tube beyond the top and bottom discs andcooperating with the spacers to hold said discs in assembledrelationship with the tube.

References Cited in the file of this patent UNITED STATES PATENTS865,980 Garland Sept. 10, 1907 1,116,322 Pampe Nov. 3, 1914 1,636,115Von Platen et a1. July 19, 1927 1,739,544 Cracknell Dec. 17, 19292,185,001 Nelson Dec. 26, 1939 2,326,243 Meyer Aug. 10, 1943

